It is softball season in Springfield and many of the workers at Springfield Nuclear Power Plant are reluctant to sign up for the Power Plant team due to their previous unsuccessful year. Homer reveals that he has a secret weapon, a homemade bat named "Wonder Bat" and his co-workers eagerly join the team. Thanks in large part to Homer, the team goes through its season undefeated and earns the right to play in the championship game against the Shelbyville Nuclear Power Plant.
Mr. Burns makes a million dollar bet with Aristotle Amadopoulos, owner of the Shelbyville plant, that his team will win. To secure victory in the game, Mr. Burns decides to hire major league stars and assembles a team that includes Shoeless Joe Jackson, Pie Traynor, Harry Hooper, Honus Wagner, Cap Anson, Nap Lajoie, Gabby Street, Mordecai "Three Finger" Brown, and Jim Creighton (the last of whom had been dead for 130 years). Waylon Smithers informs Mr. Burns that the players he picked have all retired and died, and so Mr. Burns changes tactics and orders Smithers to find some current superstar players. He hires nine Major League Baseball players — Roger Clemens, Wade Boggs, Ken Griffey, Jr., Steve Sax, Ozzie Smith, Jose Canseco, Don Mattingly, Darryl Strawberry and Mike Scioscia — and gives them token jobs at the plant so that they can play on the team, much to the dismay of the plant workers who got the team to the championship game in the first place.
Mr Burns hires a hypnotist to train the team, and they all mouth back his words (such as 'You will beat Shelbyville') in unison ('We will beat Shelbyville') until the hypnotist says 'You will give 110%', at which point the team mouth back, still in perfect unison, 'That's impossible. No one can give more than 100%. By definition, that is the most anyone can give'.
However, before the game, eight of the nine all-star players suffer unrelated misfortunes that prevent them from playing: Clemens suddenly behaves like a chicken due to the hypnotist's incompetence, Boggs is knocked unconscious by Barney after a bizarre argument at Moe's Tavern (over who was England's greatest Prime Minister, Lord Palmerston or Pitt the Elder), Griffey, Jr. takes an overdose of nerve tonic, resulting in an extreme case of gigantism, Sax is arrested and put in jail for every unsolved murder in New York City, Smith disappears in the "Springfield mystery spot", Canseco is too busy rescuing a woman and her possessions from a fire, Mattingly is kicked off the team by Mr. Burns due to sideburns only he can see, and Scioscia is hospitalized due to radiation poisoning from the plant, having taken his token job all too seriously. Mr. Burns is forced to use his original employees, along with Strawberry, the only star who can play. He made a speech that he knows that his team hated him for what he did to them and he tells them to win. Homer remains on the bench as Strawberry plays his position.
With the score tied and bases loaded with two outs in the bottom of the ninth inning, Mr. Burns elects to field a right-handed hitter against a left-handed pitcher and pinch hits Homer for Strawberry. The very first pitch hits Homer in the head, rendering him unconscious, but forcing in the winning run. The team wins the title and Homer, still unconscious, is paraded as a hero. Smithers holds the trophy. Mr. Burns thinks about it. Homer lying on the ground.